tuple contents are not dynamically checked

[bennn]

If a variable is annotated with a tuple type, Retic does not dynamically check the contents of the tuple at dereferences.

A program:

def f(x:(Int,Int))->String:
  return x[0] + x[1]

retic -p

def f(x):
    check_type_tuple(x, 2)
    return check_type_string((x[0] + x[1]))
f = check_type_function(f)

---

Sure tuples are immutable, but:

• an untyped context could supply a tuple containing bad values to a typed function (Example 1)
• tuples can contain mutable values (Example 2)

Example 1

def f(x:(Int,Int))->String:
  return x[0] + x[1] # Not sure why this type checks

def main(x)->String:
  return f(x)

main(("A", "B"))

Example 2

def g(x:(List(Int),Int))->(List(Int), Int):
  x[0][0] = "yolo"
  return x

print(g(([0], 0)))
# (["yolo", 0])